Brighamia insignis, a member of the Campanulaceae (bellflower) family, is an unbranched plant 1 to 5 m (3 to 16 ft) tall with a succulent stem that is bulbous at the bottom and tapers toward the top. The fleshy leaves, which measure 12 to 20 cm (5 to 8 in) long and 6.5 to 11 cm (2.5 to 4.5 in) wide, are arranged in a compact rosette at the apex of the stem. Fragrant yellow flowers are clustered in groups of three to eight in the leaf axils (the point between the leaf and the stem), with each flower on a stalk 1 to 3 cm (0.4 to 1.2 in) long. The hypanthium (basal portion of the flower) has 10 ribs and is topped with five oval or loosely triangular calyx lobes (partially fused sepals) 0.5 to 1 mm (0.02 to 0.04 in) long. The yellow petals are fused into a tube 7 to 14 cm (2.8 to 5.5 in) long and 3 to 4 mm (0.1 to 0.2 in) wide, which flares into five elliptic lobes. The fruit is a capsule 13 to 19 mm (0.5 to 0.7 in) long which contains numerous seeds.